Has the OP considered that the issue seems to be the Adafruit library. Adafruit has an active presence on GitHub. If one went to github and found the AdaFruity neopixel page and one was to open up a issue, posting the code and the error message. That, in short order, the person who's job it is to maintain the code will read the issue and follow up on it.
OR.
The OP can wait here for the Adafruit person to find this post and respnd. Good luck.